PARIS — France should limit its international partners to two or three nations when entering a cooperative arms program, and just one prime contractor should be picked, the National Audit Office said in a report on European cooperation in arms procurement.

Furthermore, the April 17 report emphasized the need for partners to “share the same political will to invest steadily,” and for France to be prepared to assume project management.

France should also grant a larger role to OCCAR, a European project management agency, and only launch a program when the “realism” of budgetary support could be assured, the office said. The Direction Générale de l’Armement procurement office should set up an office to track moves by the European Union toward a European defense policy and setting up research funds for military technology, the office said.

The recommendations were based on the office’s study of French gains and losses in major European programs:

- Aster surface-to-air missile

- A400M transport plane

- Tiger attack helicopter

- NH90 transport helicopter

- FREMM multimission frigate

- Aircraft carrier

Generally, technology in the weapon systems is advanced but costly and delays delivery, which puts a strain on the services, the report showed. A late delivery was only partly due to technological problems as France also slowed development due to budgetary strain.

On average, a 15-20 percent cut in a program budget led to a drop of 30-40 percent in the number of units in the program, the report said.

“The Aster is a success, despite very long delays in development,” the office said. The prime contractor, MBDA, has restructured to bring together “the best European capability” and partner nations agreed to requirements.

Britain, France and Italy are partners, with the British Royal Navy arming the Type 45 air defense frigate with the Aster missile.

The A400M carries large loads and flies long distance but the prime contractor has yet to deliver all the tactical capabilities, the report said. Development is still continuing amid “sometimes tense relations” between the client nations and Airbus.

The Tiger is a “costly technological success,” the report said. A budgetary burden led partner nations France and Germany to slash orders on the combat helicopter. The French unit cost of the Tiger rose 44 percent in 2005 when Paris cut the planned order to 120 from 215. Unit cost rose a further 39 percent after procurement fell to 71 units.

The French unit cost for the NH90 rose 28 percent as the orders fell in 2013 to 101 from 160 units. There are 22 versions of the transport helicopter, reflecting specific requirements of the client nations.

France cut its order for the FREMM to eight from an initial fleet of 17 multimission frigates. France and Italy shared the development cost, while Italy is holding on to an order for 10 units.

In a failed attempt at European cooperation, France in 2008 backed out of a plan to build with Britain a common aircraft carrier. The two partners would have shared development cost and bought common equipment. But the then president, Nicolas Sarkozy, pulled out of that project, which cost France €200 million (U.S. $246 million) in development work.

France has steered toward teaming with only two or three core partners after difficulty on the A400M, on which there are seven client nations — Belgium, Britain, France, Germany, Luxembourg, Spain and Turkey. Airbus has booked charges of €8.5 billion on that program.

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